Sustainable streets and highways

June 2014 » Project + Technology Portfolio » Environmental
Milestones on the road toward the ‘triple bottom line’
Hal Kassoff

Reconfiguration of I-71 through downtown Cincinnati eliminated the perceived barrier between downtown and the riverfront by adding overpasses for pedestrians and vehicles and reclaimed about 30 acres for mixed-use development adjacent to the river-facing part of downtown, including a new Cincinnati Reds baseball stadium and new Bengals football stadium.

Sustainable streets and highways is an idea that is here to stay. During the last decade, we have increasingly come to view transportation in all forms as a means to improve communities through the application of sustainable development principles and practices that have a positive impact on social, economic, and environmental conditions — a concept known as the “triple bottom line.” And while we haven’t forgotten our primary focus as transportation professionals, we have come to recognize that the best projects reflect a sense of parity between transportation functionality and triple-bottom-line sustainability. This is a brief look at how far we’ve come, where we’re heading, and three exemplary milestones along the way. 

A little more than a decade ago, a number of Parsons Brinckerhoff professionals began talking about sustainable transportation. It began as a sustainability initiative in the national planning practice, where it resonated with the early successes of the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) rating system. And it clearly resonated with the inherent sustainability benefits associated with public transportation.  

When it came to roadways, the idea of sustainability was met with a degree of cynicism from two sides: some engineers saw sustainability as another way for environmentalists to oppose their projects, and some environmentalists argued that roads were simply antithetical to sustainability. 


The 14th Street streetscaping project links together cultural, municipal, and commercial facilities within the downtown Denver central business district.

The obvious need to shed light on whether and how sustainability can be related to roadways prompted Parsons Brinckerhoff to present a series of seminars for clients and our own professionals during the last decade. Its initial title was “Sustainable Highways: Opportunity or Oxymoron?” More than a few attendees confessed that they saw sustainable highways as an oxymoron. A few were less tactful.  

It’s good to be able to say that we’ve come a long way. 

As the concept of sustainability has gained momentum, we have seen a broadening in the perspective of engineers in their approach to improving streets and highways. We also see community stakeholders and environmental advocates more willing to entertain the possibility that road projects, the vast majority of which involve existing facilities, have the potential to result in better outcomes for the natural as well as the built environment. We are both witnesses and participants in a distinct transformation: from focusing nearly exclusively on transportation functionality tempered only by compliance-driven mandates to avoid, minimize, and mitigate harm, toward a more balanced approach that seeks opportunities to enhance our economic well-being (including transportation functionality), the natural environment, and the social condition of our communities.  

Inspired in no small way by the success of LEED, a number of voluntary self-evaluation tools and third-party rating and certification systems have been developed for transportation (particularly streets and highways) and infrastructure in general. These  include the Federal Highway Administration’s Infrastructure Voluntary Evaluation Sustainability Tool (INVEST), the New York State Department of Transportation’s Green Leadership In Transportation Environmental Sustainability (GreenLITES) program, and the Greenroads Foundation’s Greenroads Rating System. 

An Institute for Sustainable Infrastructure (ISI) was created through the combined efforts of the American Society of Civil Engineers, the American Council of Engineering Companies, and the American Public Works Association. ISI’s ENVISION is a sustainability assessment tool applicable to all forms of infrastructure. These developments reflect the trend among civil engineers in general and transportation professionals of all disciplines who are increasingly embracing sustainability as a unifying framework for addressing how our work fits into the broader, longer-term picture reflected by the triple bottom line.


The new 14th Street streetscape in Denver balances vehicular, transit, bicycle, and pedestrian requirements to create a more vibrant downtown thoroughfare.

Following is a look at three projects — among many in our field — that exemplify the evolution of sustainable streets and highways during the last 10 years or so.  

Cincinnati’s Fort Washington Way defines ‘parity’

Well before sustainability was even a fully realized concept in the highway business, the reconfiguration of an interstate highway through Cincinnati provided the city with a vastly more functional principal arterial, freed up land for downtown development, enhanced local circulation and long-planned access to the waterfront, and accelerated environmental and health-related public infrastructure improvements. 

Downtown Cincinnati had been largely severed from one of its greatest assets, the Ohio River, by I-71, a congested highway with serious safety problems. By taking a comprehensive approach to improving the highway, the City of Cincinnati and the Ohio Department of Transportation came up with a project that not only fit well in its setting, but managed to facilitate implementation of a broader vision for the river-oriented part of downtown Cincinnati.

The reconstruction dramatically reconfigured I-71 by removing closely spaced access points that bogged down traffic and increased crashes. The right-of-way was reduced by one third with the use of retaining walls for the low-lying profile. The perceived barrier between downtown and the riverfront was virtually eliminated by adding overpasses for pedestrians and vehicles, and the visual character of the road was greatly enhanced. The project improved safety and capacity for both local and through traffic and reclaimed about 30 acres for mixed-use development adjacent to the river-facing part of downtown, including a new Cincinnati Reds baseball stadium (the Great American Ball Park), the new Bengals football stadium (Paul Brown Stadium), a museum (National Underground Railroad Freedom Center) and a portion of Cincinnati Riverfront Park.  


The Presidio Parkway includes new steel and concrete bridges and two cut-and-cover tunnels that will create a continuous pedestrian-accessible landscaped area from the Main Post to Crissy Field. Pedestrians and bicyclists will benefit from numerous new opportunities to cross over or under the parkway to access the shoreline.

A Parsons Brinckerhoff-led team supported the City of Cincinnati by providing planning, design, and construction/program management services. Design features included a new transit center; foundations for a future urban deck to cover the freeway; retaining walls sloped back and faced with precast concrete architectural panels to provide an open feeling; two pedestrian-scale, cable-stayed bridges to visually anchor each end of the corridor; planting strips placed along pedestrian bridges; and rows of trees lining Second and Third streets to bring greenery to the urban downtown area. Additionally, as an “opportunistic” health and environmental enhancement, the project accelerated the elimination of an antiquated combined sewer system in the downtown by incorporating its concurrent reconstruction. 

Fort Washington Way opened to traffic in August 2000. Last year, the Cincinnati Central Riverfront Plan — of which Fort Washington Way is a key component — received the American Planning Association’s National Planning Excellence Award for Implementation. This award was a validation of the initial vision and the ultimate reality of the Fort Washington Way project, and the broader context which it succeeded in enhancing.

A ‘Greenroad’ revitalizes a downtown Denver street 

A downtown Denver streetscaping project for the 12 blocks along 14th Street between Colfax Avenue and Market Street shows how a sustainable roadway can have a positive impact on the triple bottom line. The 14th Street project is notable for the collaboration between the city and 14th Street property owners, beginning in 2005, which successfully created the Denver 14th Street General Improvement District (GID) and secured $14 million in public-private funding. 

The 14th Street project links together cultural, municipal, and commercial facilities within the downtown central business district, including the Denver Center for Performing Arts, the Denver Convention Center, the Convention Center Hotel, the Webb Municipal Building, the historic Larimer Square shopping and dining area, and new residential and hotel projects. 

The new streetscape balances vehicular, transit, bicycle, and pedestrian requirements to create a more vibrant downtown thoroughfare. Included in the streetscape are expanded sidewalks to accommodate outdoor cafés and street-front shopping and dining, more than 200 trees, flower planters, and better pedestrian lighting, all maintained by the GID. Motorized and non-motorized “customers” can now share the street more harmoniously thanks to a dedicated bicycle lane and new bike racks at key locations, as well as a “flex-lane” that allows on-street parking during non-peak times and adds a traffic lane during peak hours.

Parsons Brinckerhoff acted as prime consultant on the project, providing a final design based on extensive stakeholder input and assisting in the formation of a GID, and supported the city during construction. Completed in November 2012, the 14th Street project subsequently became the first street in Colorado to be certified by Greenroads. 

Presidio Parkway: A regional gateway for the Bay Area 

Presidio Parkway, which is replacing the antiquated and dysfunctional Doyle Drive, was envisioned as a roadway “lying gently on the land,” tucked into the natural contours of the Presidio of San Francisco and the Golden Gate National Recreation Area, one of the nation’s largest and most important urban parks. The new parkway, expected to be completed in 2016, will be a dramatic regional gateway for travelers from North Bay communities as they cross the Golden Gate Bridge and continue into San Francisco, while at the same time providing a scenic approach to the Golden Gate Bridge for travelers from the city. 

Parsons Brinckerhoff has supported the San Francisco County Transportation Authority (SFCTA) in the $1 billion project for more than two decades, producing environmental, feasibility, and design studies for the project. In a joint venture with Arup, Parsons Brinckerhoff contributed final design and construction support services during Phase I. 

Currently, Phase II of construction is being performed under a public-private partnership by Golden Link Concessionaire, with which Parsons Brinckerhoff has worked closely on behalf of SFCTA and the California Department of Transportation.   

When fully completed, the Presidio Parkway will provide three travel lanes in each direction — two 11-foot lanes and one 12-foot lane to accommodate buses — separated by a landscaped median ranging from 16 to 41 feet, as well as a direct access connection to the Presidio. Wider lanes, the new median, and continuous shoulders will improve safety. Pedestrians and bicyclists will also benefit from numerous new opportunities to cross over or under the parkway to access the shoreline.

Other project elements include new steel and concrete bridges, two cut-and-cover tunnels that will create a continuous pedestrian-accessible landscaped area from the Main Post to Crissy Field, and an at-grade roadway with landscaped berms, not only aesthetic in appearance, but also designed to withstand a magnitude 8 earthquake.

The project team has created a roadway far superior to the pre-existing highway, and has done so in a way that minimizes impacts to biological, cultural, and natural resources; respects the setting within the Golden Gate National Recreation Area; meets the needs of the surrounding neighborhoods; and provides a safer driving experience. In short, the roadway is better than before in every respect.

The next mile: What might be envisioned

If the progress of the last decade is any indication — and if these three examples reflect the underlying change that appears to be taking hold — we will see continued progress in the sustainable development, renewal, and management of the street and highway backbone of our multimodal transportation system. The road ahead seems clear: The growing positive response to the principles and practices of sustainability among transportation professionals and the customers they serve are signaling a green light in embracing the link between streets and highways and the broader, triple bottom line purposes they must serve — sustaining the planet, its people, and the prosperity we all seek.

Hal Kassoff is a senior vice president and Highway Market leader for Parsons Brinckerhoff (pbworld.com) in Washington, D.C. He can be contacted at kassoff@pbworld.com.


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